Many of us have been waiting for some official guidelines regarding the new purple paint law; now we have them:
https://extension.purdue.edu/article/29407
I will likely begin using purple paint to mark boundary lines for my clients in the near future. If you have any questions give us a call or refer to this article. I recommend using occasional signs in addition to the purple paint until the general public becomes more aware of what this all means. I know many law enforcement agencies are still largely unaware of this law, so enforcement may be hit or miss for a while.